body,html{
  width: 98%;
  height: 98%;  
}
.wrap{
  width: 100%;
  height: 100%;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
}
.header{
  display: flex;
  justify-content: space-between;
  align-items: center;
  width: 500px;
  height: 60px;
}
button {
  background-color: #4CAF50; /* Green */
  border: none;
  color: white;
  padding: 5px 15px;
  border-radius: 5px;
  text-align: center;
  text-decoration: none;
  display: inline-block;
  font-size: 16px;
  cursor: pointer;
}